Wisteria frutescens 'Amethyst Falls' (American Wisteria) is a compact, native deciduous vine known for fragrant, 4- to 6-inch cascading lavender-blue flower clusters. Unlike aggressive Asian wisteria species, it is well-behaved, less invasive, blooms heavily in late spring with repeat summer flushes, and thrives in USDA zones 5 through 9.